74 Hereditary angioedema revealed by compartment syndrome

Abstract Background Hereditary angioedema (HAE) can present with a wide spectrum of clinical symptoms, including articular features like the compartment syndrome. Objective We present the peculiar case of a young female patient suffering from this rare complement system disorder and presenting as a « wrist oedema ». Methods A 14-year-old girl was admitted in the emergency room during a night shift. She presented with acute compartment (wrist) syndrome due to edematous compression of the median nerve, associated with a typical personal history of HAE. It resolved within 6 h with IV steroids and hyperhydration. The quantitative and qualitative C1 INH esterase returning negative, the diagnosis of HAE type III was made. The patient was treated with long-term treatment based on Danazol, (the most frequently prescribed attenuated androgen to treat HAE). Results HAE is due to the deficiency or dysfunction of the C1 inhibitor protein (quantitative or qualitative deficiency). A new nomenclature has replaced the initial use of denominations HAE type 1, 2 or 3; to speak rather of HAE with a deficient C1 inhibitor (type 1), with a dysfunctional C1 inhibitor (type 2) or with a normal C1 inhibitor (type 3) Type 3 HAE is rare and difficult to treat. It may respond to anti-estrogenic drugs such as progestins and especially to androgens; specific (very expensive) molecules do exist and act directly on the bradykinin pathways Conclusion A compartment syndrome may reveal extremely rare conditions such as hereditary angioedema. Early recognition and management are the guarantee of a preserved functional prognosis.


Background
Multisystem inflammatory syndrome in children (MIS-C) presents with fever, shock, rash, abdominal pain and raised inflammatory markers, as well as common features of inflammatory childhood illnesses. In the acute setting, especially in countries where infectious diseases are common differential diagnoses, it is challenging to diagnose MIS-C. Therefore, data differentiating MIS-C from other inflammatory and/or febrile diseases at presentation is needed. Methods Prospective data was collected from children admitted to the Red Cross War Memorial Children's Hospital in Cape Town, South Africa from May 2020 to end November 2021 where MIS-C was part of their differential diagnoses. Clinical features on the day of admission were compared between children with confirmed MIS-C (MIS-Cþ) and those with alternate diagnoses (MIS-C-).

Results
In this time period, 60 children were MIS-Cþ and 34 were MIS-C-. There was no significant difference in age (p ¼ 0.321), sex (p ¼ 0.525), ethnicity (p ¼ 0.279), or in the frequency of comorbidities (p ¼ 0.151) between the two groups. The presence of conjunctivitis (OR ¼ 8.12), rash (OR ¼ 8.67), tachycardia (OR ¼ 2.8) and oral mucositis (OR ¼ 3.75) was associated with MIS-Cþ while abdominal pain and hypotension were not. MIS-Cþ had statistically higher median C-reactive protein (CRP), pro-brain natriuretic protein (pro-BNP) and ferritin, and lower median lymphocyte count, platelet count and sodium levels than MIS-C-. Ferritin discriminated MIS-Cþ well (AUC ¼ 0.86) with a 94% sensitivity and 60% specificity at a cut off of > 195ng/l. Sodium had an AUC of 0.72, with a 70% sensitivity and 71% specificity at a cut off of < 132.5 mmol/l. CRP did not distinguish MIS-C well (AUC ¼ 0.52) and although they had good AUC, platelet count and pro-BNP had cut off values in the normal range decreasing clinical utility.

Conclusion
We provide evidence for the use of accessible clinical and laboratory variables for the diagnosis of MIS-C in diverse settings.

Implications
These data will aid clinicians to do a rapid diagnosis (and ultimately treat earlier) of patients with MIS-C in the acute setting, especially those in under-resourced settings. 72  Background Primary dysautonomia is a disorder of the autonomic nervous system with nonspecific manifestations, mainly affecting blood pressure and heart rate.

Objective
We report the diagnostic odyssey in an 11-year-old girl starting with arthralgia and leading to the final diagnosis of a rare dysautonomia.

Methods
A 13-year-old girl, with no pathologic history, was admitted to pediatrics for diffuse arthralgia without clinical inflammatory signs. Biological exploration unmasked a morning proteinuria without hypoalbuminemia and with a normal electrophoretic profile, microcytic anaemia and orthostatic hypotension authenticated during his hospitalization. Exhaustive explorations were undertaken (including autoimmune panel, ophthalomological examination, full metabolic screen and even renal biopsy), without any conclusive result.

Results
The development-after one year of follow up-of arterial hypertension, associated with orthostatic hypotension and proteinuria, points toward the extremely rare defect in baroreceptors. The management, in collaboration with the cardiology department, enhanced the patient's quality of life with a reduction in hypertensive peaks. An appropriate lifestyle also amended the intensity of orthostatic hypotension. The close multidisciplinary follow-up over >48 months is reassuring.

Conclusion
The peculiar baroreceptor defect in a context of dysautonomia should be kept in mind in the (long) list of differential diagnosis of arthralgias, as joint pain can be triggered by dysautonomia. Management is mainly symptomatic. Background Systemic scleroderma (SSc) is a rare generalized connective tissue disorder of poorly understood aetiology resulting in systemic fibrosis. It affects mainly women, usually in adulthood, but can occur at any age, although it is rare in children. Its prognosis is conditioned by cardiopulmonary involvement, which is the primary cause of mortality. Some innovative therapies have improved the management of this orphan disease. We report an observation of a 14-year-old child with systemic scleroderma. Observation Child B.Z, 14 years old, without any particular history, consulted for a Raynaud's phenomenon that had appeared 4 months earlier. Clinical examination reveals localized skin sclerosis on the face and extremities of the upper limbs (Rodnan score ¼ 11), associated with inflammatory-type arthralgias. Biologically: SV ¼ 38 mmH1, CRP ¼ 87 mg/l, FAN at 1/320 and positive Anti-Scl70. Periungual capillaroscopy showed megacapillaries with altered capillary architecture. The frontal chest X-ray did not reveal any interstitial syndrome, the cardiac ultrasound was without abnormalities (no PAH). The diagnosis of SSc was retained, the patient was put on calcium channel blockers (Diltiazem at a dose of 120 mg/d) associated with dietary rules and NSAIDs on demand with good improvement. Conclusion Very few cases of juvenile SSc have been reported in the literature. Its diagnosis should be based on the same ACR-EULAR 2013 criteria as those for adults. Its prognosis is conditioned by visceral damage which must be diagnosed and treated early.

Background
Osteogenesis imperfecta, or ''glass bone disease'', is a rare genetic disorder due to an abnormality in the production of type 1 collagen. It is characterised by bone fragility and low bone mass, leading to repeated fractures. Osteogenesis imperfecta (OI) can be classified into several types ranging from lethal at birth to benign forms that may be discovered incidentally in adulthood. We report four observations of OI that caught our attention. Observation 1: Mr H.A, aged 15 years, with no particular pathological history (atcd), he presented since the age of 4 years old iterative lowenergy fractures (06 fractures). The clinical examination finds dorsal scoliosis, deformities of the long bones, blue staining of the sclerae. Radiography showed diffuse bone hypertransparency, thinned cortices and curvature of the long bones. Osteoporosis with a Z-score of -3.8 DS in the spine and -3.1 DS in the femur on bone densitometry (BMD). The patient received 20 courses of pamidronic acid at a dose of 07 mg/kg/year with good clinical (decrease in the number of fractures) and osteodensitometric improvement and good tolerance. Observation 2: Mr D.A, 16 years old, without any particular pathological atcd, the onset of the disorders goes back to the age of 13 years marked by the installation of repeated fractures following minimal trauma. The patient presents with growth retardation, deformities of the long bones and blue sclera. Radiography showed diffuse bone hypertransparency, thinned cortices, curvature of the long bones with bilateral coxa profonda. BMD showed osteoporosis with a Z score of -4.8DS. He was treated with pamidronic acid at 07 mg/kg/year (09 courses) with satisfactory improvement and good tolerance. Observation 3: Mr A.N aged 41 years with no particular pathological atcd. The history of the disease shows repeated low-energy fractures (06 fractures) since the age of 11 years. On clinical examination, there is an exaggerated kyphosis, blue sclera and bilateral hearing loss on the right. On imaging, diffuse bone hypertransparency, thinned cortices, curvature of the long bones and right acetabular protrusion were noted. On BMD, osteoporosis with a Z-score of -4.0 DS at the spine and femur. The patient received zoledronic acid 04 mg/ 06 months. The patient improved well with a decrease in the number of fractures and an improvement in bone densitometry. Observation 4: Mrs B.Z aged 40 years without any particular pathological atcd, having made iterative low energy fractures since the age of 01 month (05 fractures). The patient presents a dorsal scoliosis, deformations of the long bones, growth retardation, blue sclera and translucent teeth. The radiograph shows diffuse bone hypertransparency, thinned cortices and curvature of the long bones. BMD and adequate treatment were not done as the patient was lost to follow-up.

Conclusion
Osteogenesis imperfecta is a rare disease with a polymorphous clinical expression. Late diagnosis delays the initiation of adequate treatment and consequently the persistence of fractures. Bisphosphates improve bone mass and reduce the incidence of fractures and are generally well tolerated.